Hi Guys, Great resource hear, thanks for all the help and info.

I have a small two story house (11' x 50') with an exposed ceiling where you can see the joists and sub floor. I like the look of this exposed ceiling and what to keep it that way. The problem is that when you are upstairs you can hear everything that is happening on the floor below. I figured since I need to sound proof from the top floor I would add in radiant floor heating and seal off the floor completely.

My main objectives are:

1. Sound proof top floor from bottom floor.
2. Install in floor radiant.
3. Keep costs down, I'm not a rich guy.

I've been reading and reading and reading. I got quotes for a gypcrete pour and warmboard. But both of these are in the $3000 and up range.

Are there dry sandwich methods that will be very close or on par with the sound proofing and heat efficiency a gypcrete pour?

There are a lot of variables here that I'm not mentioning, but I thought I ask this question right off the bat to see if anyone has experience with this.

Thanks for the help.

There is the diy sandwich method with sleepers and plates.

Sounds like you need to prioritize cost, sound, and appearance.

Sound proofing is only done by insulation or distance how much depends on how quiet you want it. Whats going to be the floor covering.

First and fore most you need a heatloss calc. to get started in the right direction.


The problem is not wanting to insulate the underside you end up with backlosses to the floor below. Maybe overheating that space, and underheating the second floor.


Details please.

Gordy

Hi Gordy thanks for the insight.

The heat loss calcs. you mentioned brings up a good point. My house is semi-detached and the main wall is an uninsulated double brick wall.

The ceiling height on the bottom floor is 10' tall and that's where the beams start... true 2x8's and the sub floor on top of that.

Currently, there is forced air from a mid
efficiency furnace supplying heat for both floors.

My plan is to use a product called green glue on top of the sub floor, followed by a rubber underlay called duracoustic, then build the dry sandwich with pex on top of the underlay.

I called up the green glue guys and they weren't familiar at all with gypcrete. So they couldn't tell me whether green glue would perform better than gypcrete.

I like the idea of using gypcrete but I think its going to be significantly more expensive to put down an underlay + gypcrete than for me to build a radiant floor with sound proofing products integrated.

The finished floor on top is just going to be laminate for the time being, then a few years down the road I might put in engineered hardwood.

To pour the gypcrete its going to cost me $2452 + taxes, then another $800 for the duracoustic underlay.

I'm thinking to build a dry sandwich will cost me $400 for the green glue, $800 for the underlay, and probably $300 - $500 for the drywall or plywood (I could be wrong on the drywall/plywood costs though... need enough to cover 500 sq feet).

So the gypcrete scenario comes in at around $4000 but with the dry sandwich I can do the work myself with some friends for under $1700?

STC ratings for an exposed ceiling, just a wood subfloor and hardwood are about 33 STC. If I add the green glue that might bring up to 40 STC, then the underlay might add another 7 bringing it up to 47 STC. Then, I'm hoping the dry sandwich and laminate bring it up 5 more points to about 52 STC.

I'm going to try searching for STC numbers for just a subloor with underlay and gypcrete.

Thanks for the help, sorry I've gone on for so long. Radiant is a very in depth subject, even more so when you're combining it with soundproofing... kill two birds with one stone.